Alpine ski

ABSTRACT

A ski adapted for the practice of alpine skiing includes a front portion, a rear portion, and a central portion, the central portion being adapted to receive an assembly for binding a boot to the ski, which is inserted between the front portion and the rear portion. The front portion includes a maximum width having a value ranging between 135 mm and 165 mm, and the difference between the maximum width value of the front portion and the maximum width value of the rear portion is greater than 25 mm and less than 55 mm. The rear portion can include a maximum width value ranging between 90 mm and 130 mm, and the central portion can include a smaller width value ranging between 60 mm and 130 mm.

CROSS-REFERENCE TO RELATED APPLICATION

The instant application is based upon the French priority PatentApplication No. 09.05587, filed Nov. 20, 2009, the disclosure of whichis hereby incorporated by reference thereto, and the priority of whichis hereby claimed under 35 U.S.C. §119.

BACKGROUND

1. Field of the Invention

The invention relates to gliding apparatuses, in particular skis adaptedfor the practice of alpine skiing.

2. Background Information

A pair of alpine skis is comprised of two boards that are substantiallyidentical or at least symmetrical with respect to one another. One ofthe basic techniques of skiing requires the skier to maintain his/herbody in a plane perpendicular to the ground in order to move along astraight line, or to tilt his/her body toward the inside of the turn inorder to turn. This has a direct consequence on the positioning of theskis with respect to the ground. When the skier moves along a straightline, the skis are flat on the ground, resting on the gliding surface ofthe bottom layer, referred to as the sole. When turning, the skierinclines his/her skis with respect to the ground. In this case, It isthe lower outer corners; commonly referred to as the running edges (orbottom edges) which come into contact with the ground or snow. Whenviewed from above, the contour of the running edges is called thesidecut. It is to be understood from the preceding that, among thevarious characteristics that constitute a ski, the geometry of thesidecuts plays a determining role in the behavior of the ski. Inparticular, the sidecuts define the type of steering to be applied bythe skier. The running edges are in particular defined as being thelower edges of the ski that are located between the widest zone of theski at the front of the ski and the widest zone of the ski at the rear.

The methods of manufacture of alpine skis, as well as their geometricaland structural dimensions, have evolved since the beginning of alpineskiing. New developments sometimes have been driven by changes in thepractice of the sport and/or sometimes in the manufacturing processes.

Skis sold until the 1980s were relatively long, straight, and narrow.The sidecuts had very large radii, typically greater than 30 meters (m).The maximum width in the front portion of such skis and the maximumwidth in the rear portion of such skis had substantially the samevalues. Furthermore, the zone of the ski with minimal width, also calledthe narrow point, or waist, was in the middle of the ski, i.e., in thearea of the boot binding zone. Such skis were suitable for use on thetrails of that time and they were particularly adapted to the skiingtechniques used at the time. Each turn required the skier to reduce thepressure exerted on the skis, enabling the skier to turn, i.e., steer,the skis. To a certain extent, such skis remain well-adapted to skiingat high speed, in a straight line and on-piste. Standing apart free fromthe shape of skis sold mainly until the 1980s, some independentinventors proposed different shapes, which were however unsatisfactory.An example of these various shapes is disclosed in the patent documentCH 503 501, which explains that the reduction in the width of the heelportion, up to a value of 5 centimeters (cm), was compensated for by thewidening of a groove in the sole. Such geometry lacks versatility, inparticular due to the small width in the area of the heel. Moreover,making a groove with a variable width would render the ski particularlyexpensive to manufacture.

In the early 1990s, the patent document DE 41 12 950 discloses a newshaped ski having an objective of improving the behavior of the ski whenturning and to enable faster direction changes. This shaped ski ischaracterized in that the concave portion is reduced lengthwise and hasa reduced radius compared to what was prevalent at the time. Thisconcave portion is substantially centered longitudinally in the middleof the ski. The ski sidecuts are constituted by rectilinear portionsbelow and above the reduced concave portion. The rectilinear portions ofthe sidecut, the length of which ranges between 10 and 20 cm, connectthe concave portion to the shovel, on the one hand, and to the heel, onthe other hand. Such geometry produces a ski whose turning ability canbe improved, but whose behavior is not fluid.

Beginning in the 1990s, the sidecuts became deeper and the radiishorter. The skiing technique also changed so as to reduce, eveneliminate, the need to lighten the pressure when turning. These skis areparticularly adapted to practice on a packed ski trail. The patentapplication EP 579 865, for example, describes such a ski, in which theminimal width is in the area of the bindings, in the central portion ofthe ski, and is equal to 63 millimeters (mm), while the width at theshovel, i.e., the front portion of the ski, and the width at the heel,i.e., the rear portion of the ski, are equal to 110 mm and 100 mm,respectively. Skis of this type made it possible to bring about a newskiing technique, referred to as carving, which involves cutting intosnow through the turns. To promote ski carving, it is important to havevery deep sidecuts, and consequently shorter radii. When these skisappeared on the market, they were termed parabolic skis because thegeometry of their sidecut was similar to a parabolic shape; the maximumwidth in the area of the shovel and that in the area of the heel wererelatively substantial and substantially the same, within 10 or 20 mm asin the example mentioned above, whereas the minimal width in the area ofthe central portion was much smaller. Currently available skis aremainly based on this type of geometry. Skis with very deep sidecuts havea satisfactory behavior on-piste but a very poor behavior off-piste.Indeed, the sidecuts with very short radii cause the ski to engage incurves too easily in soft snow. It is therefore very difficult to ski ina straight line.

Skis also became shorter and thicker, as shown in U.S. Pat. No.5,603,522. This skis disclosed in this document have a length less than1730 mm, a shovel having a width ranging between 110 and 120 mm, a waisthaving a width ranging between 82 to 99 mm, and a heel having a widthranging between 105 and 115 mm, it being necessary to maintain thevariation between the width of the shovel and that of the heel between 4and 12 mm. The objective leading to the manufacture of such skis was tooptimize torsional stiffness by combining a relatively great width witha relatively small length. As a result of this preconceived purpose,these skis are not very versatile. It is difficult to design a ski withthis geometry, which can behave optimally on-piste and off-piste. It isalso difficult to design a ski according to this geometry, which can beadapted to various skiers having various technical skills and goals(beginners, leisure, competition). Shortening the length of the skis didhowever not redefine the direction which was set during the 1990's forthe parabolic skis. In fact, these skis still have the characteristicwhereby the zone of the ski with minimal width is in the center of theski, in the area of the ski boot center.

Freeride, a primarily off-piste skiing technique in virgin snow, wasintroduced in the 2000s, and specific skis have been developed bymanufacturers. These skis are very wide and have waist widths that canreach 140 mm. Of course, these skis are not versatile at all; they arevery difficult to operate on-piste and are intended for experiencedskiers. Indeed, steering a ski that is very wide in its central portionon-piste requires a substantial muscular effort and is almost impossibleto use for a beginner or a skier with little skiing experience. Suchskis are described, for example, in U.S. Patent Application PublicationNo. 2008/00042400.

One of the characteristics of the skis adapted for the discipline, orpractice, of freeride is that their shovels are substantially longer andwider than that of the skis adapted for on-piste practice. As defined inthe ISO Standard 6289, the ski shovel is the portion that is turnedupward to enable the ski to ride easily over obstacles. According to thestandard, the length of the shovel is defined by the distance separatingthe tip of the ski from the front contact line (the front limit of thecontact zone of the bottom surface of the ski on a planar surface). Onecan choose to determine this length by measuring the projection on aplanar surface, this being the projected length, or by measuring thenominal length, this being the developed length. In the followingdescription, reference to length will refer to the developed length.Furthermore, for practical reasons, the term shovel length “Ls”, as usedin the following description, means the measurement taken between theend of the ski and the line of greatest width at the shovel, and not the“end-to-contact line” distance, as provided in the standard. The portionof the ski referred to as the “shovel” in the ISO Standard 6289 will becalled the “raised zone” of the ski. The shovel and the raised zonemerge more or less along the distance between the front contact line andthe line of greatest width.

For a ski adapted for off-piste practice, or use, and in deep snow, itseems advantageous to have a high, long, and wide shovel. However, thesecharacteristics turn into disadvantages when the skier wishes to use theskis on-piste. Indeed, the mass of the portion of the ski raised off thesnow is increased with shovels of this type, which also tend to causevibrations in the ski and to weigh it down.

SUMMARY

The invention provides an alpine ski that has an optimal behavioron-piste as well as off-piste.

In addition, the ski of the invention provides, for a skier havinglittle practice and/or a weak muscular force, with the ability to skiunder any circumstances, on any type of snow, whether on-piste oroff-piste.

Further, the invention provides a new family of skis enabling a newtechnique for the practice of alpine skiing.

Still further, the invention provides a new family of skis that includea plurality of pairs of skis, all of which have an optimal behavioron-piste and off-piste, but which distinguish over one another by agreater suitability for skiing on-piste or off-piste.

A ski according to the invention is provided with a geometry thatcombines advantages of skis with deep sidecuts and those of skis withbroad sidecuts.

In addition, a ski according to the invention has a shovel that providesthe ski with an improved behavior in powder snow.

A ski according to the invention includes a front end that does notvibrate during use on-piste.

Further, the invention provides a ski that offers definitely newbehavioral characteristics, in that, e.g., the front portion of the ski(located ahead of the boot) and the rear portion of the ski (locatedbehind the boot) each has a different behavior.

To these ends, a ski according to the invention is provided that isadapted for the practice of alpine skiing, the ski including a frontportion, a rear portion, and a central portion, the latter adapted toreceive a binding assembly for binding a boot to the ski, the bindingassembly being inserted between the front portion and the rear portion;the front portion of the ski includes a portion of relatively greaterwidth, which includes, along its length, a maximum width value “S”,ranging between 135 mm and 165 mm, and in which the difference “Δt”(delta-t) between the maximum width value “S” of the front portion andthe maximum width value “T” of the rear portion is greater than 25 mm.

According to advantageous but non-limiting aspects of the invention, aski according to the invention includes a front portion, a rear portion,and a central portion; and it can incorporate one or more of thefollowing features, taken in any technically acceptable combination:

-   -   the rear portion includes a portion of greater width having a        value “T” ranging between 90 mm and 130 mm;    -   the central portion includes a portion of smaller width having a        value “C” ranging between 60 mm and 130 mm;    -   the difference “Δt” (delta-t) between the value “S” and the        value “T” can range between 32 mm and 55 mm;    -   the value “S” ranges between 140 and 160 mm;    -   the shovel has a length “Ls” ranging between 150 and 320 mm, or,        in an alternative embodiment, between 160 and 300 mm;    -   the value “P” corresponding to the width of the ski, measured at        a distance of 30 mm from the front end of the ski, is less than        60% of the maximum width value of the front portion: P<0.6×S,        or, in an alternative embodiment, less than 50% of the maximum        width value of the front portion: P<0.5×S;    -   the distance separating the boot center MC from the line of        smaller width C is greater than 150 mm, or, in an alternative        embodiment, greater than 180 mm;    -   the distance LB separating the line of smaller width C from the        line of greater width of the rear portion T is null.

BRIEF DESCRIPTION OF DRAWINGS

Other characteristics and advantages of the invention will be betterunderstood from the description that follows, with reference to theannexed drawings illustrating, by way of non-limiting embodiments, howthe invention can be embodied, and in which:

FIG. 1 is a top view of a ski according to a first embodiment of theinvention;

FIGS. 1 a and 1 b are detailed views of FIG. 1;

FIG. 2 is a side view of the ski shown in FIG. 1;

FIG. 2 a is a detailed view of FIG. 2;

FIG. 3 is a top view of a ski according to a second embodiment of theinvention;

FIG. 3 a is a detailed view of FIG. 3;

FIG. 4 is a top view of a ski according to a third embodiment of theinvention;

FIG. 5 is a top view of a ski according to a fourth embodiment of theinvention;

FIG. 6 is a top view of a ski according to a fifth embodiment of theinvention; and

FIG. 7 is a top view of a ski according to a sixth embodiment of theinvention.

DETAILED DESCRIPTION

FIG. 1 is a top view illustrating only one of the skis of a pair adaptedfor the practice of alpine skiing.

According to a known general configuration, the illustrated ski includesa gliding sole having a bottom surface, or running surface, adapted tobe in contact with snow, an inner structure, and a top portion. Asdescribed below, the ski of FIG. 1 features definitively new sidecuts.

The top of the central portion 4 of the ski receives the safety bindings5 which retain the ski boot (not shown) of the user on the ski. Thesmallest width of the central portion 4 of the ski, referred to as thewaist, has a value C equal to 88 mm in the ski of the illustratedembodiment. This is a relatively large value compared to the skisdesigned up to the early 1990s. However, this value is not as great asthe widths currently recommended for skis intended for use in powdersnow. Such a width, ranging between 60 and 120 mm, or 70-100 mm in amore limited range, provides the ski with great versatility of use andmakes it available to a larger number of users, i.e., from beginners toexperienced skiers.

FIG. 1 b illustrates a detailed top view of the central portion of theski, showing the respective positioning of the two characteristic linesof the central portion of the ski, namely, the boot center and thenarrow point. The boot center line is a marking affixed on the ski bythe manufacturer to indicate the recommended positioning of the skibindings, such that the boot, once bound on the ski, is centered on theboot center line. Unlike the skis of the prior art, the transverse lineC at the smallest width of the central portion, commonly called the skinarrow point, is set back with respect to the boot center line (MC) by avalue greater than 150 mm. In the ski illustrated in FIG. 1, thedistance LC separating the narrow point and the boot center line isequal to 271 mm.

The rear portion 3 of the ski, also referred to as the heel, has a zoneof greater width, including a value T ranging between 90 and 110 mm.Such a width enables support to be taken relatively easily at the end ofa turn, without it being necessary to exert very strong supportingforces on the running edges. In the example shown in FIG. 1, the value Tis equal to 100 mm.

The heel illustrated in FIG. 1 has a pointed shape. This shape is onlyone of the multiple shapes that the heel can take, and it is not to beconsidered as limiting the scope of the invention.

According to the invention, the front portion of the ski comprises afront portion 2, whose maximum width, having a value S, is much greaterthan the maximum width, having a value T, of the heel portion.

Tests on various sidecut geometries have shown that the effects soughtby the invention can be obtained if the difference “Δt” (delta-t)between the maximum width value S of the front portion 2 and the maximumwidth value T of the rear portion 3 is greater than 25 mm. It has alsobeen shown that these effects are amplified so as to mark a significantbehavioral difference with known skis of the prior art, as soon as thevalue Δt is greater than 32 mm. Indeed, with a value Δt equal to orgreater than 32 mm, the difference in behavior generated by the geometryof the front portion and rear portion of the ski becomes moresignificant. For reasons related to weight and space requirement, thelength of the shovel is limited to a value of 190 mm. In a particularembodiment within the scope of the invention, the maximum width of theshovel S is also limited as a function of the width of the rear portionT, such that the value Δt remains less than 60 mm, or, in an alternativeembodiment, less than 55 mm.

In the example shown in FIG. 1, the front portion 2 has a maximum widthS that is equal to 150 mm; the difference Δt is equal to 50 mm.

The ski illustrated in FIG. 1 thus has a shovel of very substantialwidth, i.e., a width that is on the same order as the shovel widths ofcurrently known skis, but which is exclusively provided for the practiceof freeride. In fact, the current freeride skis are much too wide toenable easy steering on a packed trail. Due to its wide shovel, the ski1 has a good behavior in deep snow. Moreover, it is much easier tocontrol this ski on-piste than a freeride ski. This is a particularlyversatile ski whose behavior on-piste and off-piste is optimized, inparticular due to a minimal width being equal to 88 mm in the centralportion.

A versatile ski, such as shown in FIG. 1, seeks to limit the mass of theshovel that is raised from the snow while preserving an adequate lengthfor the shovel. To this end, pointed shovels whose lines of greatestwidth in the front portion are at a relatively low height areparticularly advantageous, as explained below.

FIG. 1 a shows the “pointed” characteristic of the contour of the frontportion 2 of the ski 1. This pointed characteristic is shown by themeasurement of the ski width in the vicinity of the ski front end, i.e.,the tip 6. This measurement, designated by the reference character “P”,is taken at a distance of 30 mm (developed length) from the tip 6 of theski 1. In this example, the value of P is 55 mm.

The shovel is considered to have a pointed contour insofar as the value“P” is less than or equal to half (50%) of the maximum width of thefront portion 2, i.e., the value “S” (P≦0.5×S).

In advantageous embodiments, a pointed shovel is relatively long. In thecontext of the invention, the length “Ls” of shovel is selected to begreater than 150 mm. The skis of the invention yielding the bestperformances are those that have a shovel length ranging between 150 and320 mm.

To improve the behavioral versatility of the skis according to theinvention, pointed shovels (P≦0.5×S) are used. However, skis accordingto the invention whose shovels are moderately pointed, i.e., thosehaving a value “P” less than or equal to 60% of the value “S”, yieldsatisfactory results. Furthermore, skis having round shovels are alsowithin the scope of the invention.

FIG. 2 is a side view of the ski 1 of FIG. 1. The ski rests on a planarsurface 9, in the area of two lines, i.e., the front contact line 7 andthe rear contact line 8. The length Ls of the shovel, measured betweenthe line of greatest width and the tip 6 of the ski, is equal to 256 mmin the illustrated embodiment.

The front contact line 7 is located near the line 10 of greatest widthof the ski shovel. As shown in FIG. 2 a, this proximity translates intothe ski sole being at a height “Hs”, said height being less than 10 mm,e.g., in the area of the line of greatest width.

FIG. 1 illustrates a ski having an overall length equal to 1900 mm. Thislength is not limiting to the scope of the invention. Indeed, theparticular geometry of the invention can be easily applied to skis thatare longer or shorter than 1900 mm.

FIG. 3 shows a second embodiment of the invention. As in the embodimentdescribed above, this ski is designed for a multipurpose use on-pisteand off-piste, with a slight predisposition for ski carving, and for usein fresh snow. In the area of the rear portion, the greatest width ofthe ski, having the value “T”, is equal to 105 mm; the minimum width ofthe central portion 4, having the value “C”, is equal to 80 mm; and thegreatest width of the shovel, having the value “S”, is equal to 140 mm.

A ski is thus obtained, whose sidecuts are sufficiently deep, the radiusof the sidecut being equal to approximately 11 m. The difference betweenthe shovel width and the heel width, i.e., the value “Δt”, is equal to35 mm.

The shovel is very long, the value “Ls” being equal to 300 mm, and verypointed, the value “P” being equal to 42 mm, which corresponds to 30% ofthe greatest shovel width.

FIG. 3 a is a detailed view of the ski shown in FIG. 3, which makes itpossible to visualize the relationship between the variouscharacteristic lines of the rear half-length of the ski. The boot centerline MC is positioned at a distance LA from the line of greatest width Tof the heel. Conventionally, the length LA corresponds to a certainpercentage of the overall length of the sidecut. The line of smallestwidth of the ski in the central portion, also called the narrow pointand designated by the reference character “C” in the drawing figures, islocated between the lines MC and T. According to the invention, thedistance LC separating the lines C and MC is greater than 150 mm. Inother words, the narrow point is behind the boot, when the boot is boundon the ski.

FIG. 4 shows a third embodiment of the invention, for which the valuesS, C and T are equal to 160, 103, and 117 mm, respectively. The shovelis relatively long, the value “Ls” being equal to 300 mm. This ski isparticularly adapted for off-piste practice; and it is designated as afreeride ski with reference to one of the categories currently used bymanufacturers to brand their products.

However, due to a particularly substantial difference between the widthof the shovel and that of the heel, the value “Δt” being equal to 43 mm,the ski has a notably improved versatility when compared to the typicalskis in the freeride category.

The front portion 2 is also characterized by its “pointed” feature.Indeed, the width P, measured at a distance of 30 mm from the tip 6, isequal to 53 mm, i.e., corresponding to approximately 34% of the widthvalue “S” of the shovel.

FIG. 5 shows a fourth embodiment of the invention, for which the valuesS, C, and T are equal to 140, 68, and 90 mm, respectively. The shovelhas a length “Ls” of 190 mm and a pointed shape with a value “P” equalto 57 mm (40% of the value S). This ski is particularly adapted foron-piste practice.

However, due to a particularly substantial difference between the widthof the shovel and that of the heel, the value “Δt” being equal to 50 mm,the ski has a notably improved versatility compared to the skis that aretypically dimensioned for on-piste practice. In particular, with such aski, the user can occasionally switch to a different practice of skiingand leave the trail. Such a ski makes freeride practice more easilyaccessible to beginners or skiers having little experience.

Table 1 below recapitulates the geometrical data of a complete line ofskis according to the invention. These skis are characterized by animproved versatility compared to the skis known to date, while eachhaving a preferred field of practice.

The line of skis shown in Table 1 includes eighteen skis each having adifferent geometry, but all of which share the innovativecharacteristics of the invention. The overall length of the skis is notspecified in this table. Each ski included in this line was developedwith an average length ranging between 2000 and 1600 mm. In order toassemble this inclusive offering, the manufacturer presents each of theskis in various sizes to adapt each geometry to the weight and size ofthe users.

The first three skis in the table, which include the ski shown in FIG.5, are skis that yield their best performance on-piste due to arelatively small width at the waist. However, when the skier practicesoff-piste with one of these skis, he/she will benefit from a good liftdue to a long and wide shovel. In the case in which the ski has apointed shovel, as in FIG. 5, these skis are completely adapted forspeed and, for example, for downhill and giant slalom (GS) competitions.

The eight skis at the bottom of the table are designed mainly foroff-piste use. However, due to a minimal width in the central portionnot exceeding 130 mm, and particularly not exceeding 120 mm, these skisremain very easy to control on-piste. On-piste, these skis do notrequire any more steering effort from the user than skis especiallydesigned for on-piste practice. Also, the choice of a pointed shovel, asfor the ski shown in FIG. 4, further increases the versatility of use ofthese skis.

In the middle of the table, eight skis, in which the ratio of theon-piste aptitude to the off-piste aptitude ranges between 70/30 and30/70, are designed for on-piste and off-piste practices. The skis shownin FIGS. 1 and 3 are examples of such multipurpose skis.

TABLE 1

As described above, one of the aspects of the invention is related tothe fact that the narrow point is set back with respect to the bootcenter by a value greater than 150 mm, or, in particular embodiments,greater than 180 mm. Table 2 compiles the values of four different skigeometries sharing the same shovel and heel widths, but whose narrowpoint is in different positions.

TABLE 2 S C T Δt LB LC 160 106 125 35 515 177 160 118 125 35 400 290 160123 125 35 261 431 (FIG. 6) 160 125 125 35 0 692 (FIG. 7)

The first two lines in the table correspond to ski geometries that arewell-adapted for off-piste practice, and in which the position of thenarrow point with respect to the center boot, at 177 and 290 mm,respectively, is such that these geometries provide the ski with gooddirectional mobility.

The third line in the table corresponds to a geometry, an exemplary skiof which is shown in FIG. 6. As shown, the line of the narrow point isfar set back. The distance separating the narrow point from the line ofgreatest width of the heel corresponds substantially to one third (⅓) ofthe distance separating the line of greatest width of the heel from theboot center. The setback position of the narrow point improves thestability of the ski at high speed and, due to a difference in theshovel/heel width being equal to 35 mm, this ski maintains a goodversatility.

FIG. 7 shows a ski in which the shovel/heel difference is also equal to35 mm, but whose narrow point is set back to the maximum, i.e., up tothe area of the greatest width of the heel. In this geometry, the lineof the narrow point C and the line of greatest width T of the heelmerge. The complete sidecuts of the ski connect the narrow point C tothe line of greatest width S of the shovel. The sidecut is a curved linewhose mean radius of curvature can be greater than that of the otherembodiments of the invention. For example, the mean radius of thesidecut can exceed 30 m, even 50 m, whereby reference is made to anextended sidecut.

The ski shown in FIG. 7 offers practice versatility, in particular forthe practice of freeride, associated with excellent directionalstability.

This ski is particularly adapted for the latest category among off-pistepractices, i.e., the “Big Mountain”. The practice known as “BigMountain” involves going downhill at very high speed on very slopedmountainsides and along trajectories having large radii of curvature.

The invention is not limited to the embodiments that have just beendescribed; and it includes all of the technical equivalents that arewithin the scope of the claims that follow.

In addition, the invention illustratively disclosed herein suitably maybe practiced in the absence of any element which is not specificallydisclosed herein.

1. A ski structured and arranged for the practice of alpine skiing, said ski comprising: a front portion; a rear portion; a central portion structured and arranged to receive an assembly for binding a boot to the ski, such assembly to be mounted to the ski between the front portion and the rear portion; the front portion of the ski comprises a portion of greater width, including a maximum width value (S) ranging between 135 mm and 165 mm; a difference between the maximum width value (S) of the front portion and a maximum width value (T) of the rear portion is greater than 25 mm.
 2. A ski according to claim 1, wherein: the central portion comprises a line of smallest width and a marking of the boot center (MC) corresponding to a zone in which the binding assembly is to be centered; a distance (LC) separating the line of smallest width and the marking of the boot center is greater than 150 mm.
 3. A ski according to claim 1, wherein: the rear portion comprises a portion of greater width, including the maximum width value (T) ranging between 90 mm and 130 mm.
 4. A ski according to claim 1, wherein: a smallest width of the central portion (4) has a value (C) ranging between 60 mm and 130 mm.
 5. A ski according to claim 1, wherein: the difference between the maximum width value (S) and the maximum width value (T) is greater than 32 mm.
 6. A ski according to claim 1, wherein: the difference between the maximum width value (S) and the maximum width value (T) ranges between 32 mm and 55 mm.
 7. A ski according to claim 1, wherein: the maximum width value (S) ranges between 140 mm and 160 mm.
 8. A ski according to claim 2, wherein: the distance (LC) is greater than 180 mm.
 9. A ski according to claim 1, wherein: the shovel has a length (Ls) ranging between 150 and 320 mm.
 10. A ski according to claim 9, wherein: the shovel has a length (Ls) ranging between 160 and 300 mm.
 11. A ski according to claim 1, wherein: a width (P) of the ski, measured at a distance of 30 mm from a front end of the ski, is less than 60% of the maximum width value (S) of the front portion: P<0.6×S.
 12. A ski according to claim 11, wherein: a width (P) of the ski, measured at a distance of 30 mm from a front end of the ski, is less than 50% of the maximum width value (S) of the front portion: P<0.5×S.
 13. A ski according to claim 4, wherein: the line of the smallest width (C) of the central portion and the line of the maximum width value (T) of the rear portion are merged.
 14. A ski according to claim 4, wherein: a distance (LB) separating the maximum width value (T) of the rear portion and the smallest width value (C) of the central portion is zero. 